[BUG] Upgrading from Version 4 Throws LiteException: File is not encrypted as of Version 5.0.18 about litedb

[JKamsker]

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[jdtkw]

We have the same issue for our use of LiteDB - older releases are on LiteDB v4, and would need to upgrade to LiteDB v5 due to the published security issue. However, the upgrade bug from v5.0.18 onwards means we can't use the library.

Based on my investigation, I believe this issue is an incompatibility with the v4 format with a password and the AesStream class. Essentially, any time a v4 file is opened, it has to use the Stream class instead of AesStream. I'll test my workaround for this with your sample and if it works, I'll put it up for review and we can iterate over that.